Kidney and Recipient Weight Incompatibility Reduces Long-Term Graft Survival

[okarol]

 July 20, 2010
Kidney and Recipient Weight Incompatibility Reduces Long-Term Graft Survival

Giral M, Foucher Y, Karam G, Labrune Y, Kessler M, de Ligny BH, Büchler M, Bayle F, Meyer C, Trehet N, Daguin P, Renaudin K, Moreau A, Soulillou JP.   J Am Soc Nephrol.   2010 Jun;21(6):1022-9
Nephron mass plays an important role in providing adequate renal function, with loss of nephron mass a risk factor for later deterioration of renal function. In this study, a low ratio of the weight of the donor kidney before implantation to recipient weight was associated with worse long-term renal function and outcomes.
Related Articles:

    * Perioperative Mortality and Long-term Survival Following Live Kidney Donation
    * Preserving residual renal function in peritoneal dialysis: volume or biocompatibility?
    * Dialysis-requiring acute renal failure increases the risk of progressive chronic kidney disease

    * Share/Bookmark

Abstract:

Long-term function of kidney allografts depends on multiple variables, one of which may be the compatibility in size between the graft and the recipient. Here, we assessed the long-term consequences of the ratio of the weight of the kidney to the weight of the recipient (KwRw ratio) in a multicenter cohort of 1189 patients who received a transplant between 1995 and 2006. The graft filtration rate increased by a mean of 5.74 ml/min between the third and sixth posttransplantation months among patients with a low KwRw ratio (<2.3 g/kg; P<0.0001). In this low KwRw ratio group, the graft filtration rate remained stable between 6 months and 7 years but then decreased at a mean rate of 3.17 ml/min per yr (P<0.0001). In addition, low KwRw ratios conferred greater risk for proteinuria, more antihypertensive drugs, and segmental or global glomerulosclerosis. Moreover, a KwRw ratio<2.3 g/kg associated with a 55% increased risk for transplant failure by 2 years of follow-up. In conclusion, incompatibility between graft and recipient weight is an independent predictor of long-term graft survival, suggesting that avoiding kidney and recipient weight incompatibility may improve late clinical outcome after kidney transplantation.

http://www.nephrologynow.com/publications/kidney-and-recipient-weight-incompatibility-reduces-long-term-graft-survival

[cariad]

I read (or more accurately, skimmed) the full article to make sure I was understanding what they were trying to say correctly. I believe this actually is an important factor, and I have read articles from quite a few years back that support this data. One of these older research articles found that recipients who had male donors had on average longer graft survival, and the authors hypothesized that this was because men have larger kidneys with a higher number of nephrons. My ratio from my first would have been quite high (good) because I weighed roughly 14 kilos, and my donor probably weighed closer to 82 kilos, and likely he had a kidney to match his size.

My husband was said to have an outsized kidney (makes sense, my little boy had one kidney that was adult sized at age 3). No idea what an average kidney weighs, but I weigh about 50 kilos, so this study bodes well for my future with this graft.